Mailbox cannot be created: Unable to get default delivery transport string from /var/qmail/mailnames/.default_delivery

Symptoms

• Unable to create a new mailbox in Plesk interface with the following error:

  PLESK_ERROR: mailmng-core failed: mailmng[27218]: Unable to get default delivery transport string from /var/qmail/mailnames/.default_delivery
  mailmng[27218]: Unable to add delivery string to '/var/qmail/mailnames/example.com/email/.qmail' 
  Fatal error: plesk::SystemError(unable to modify /var/qmail/mailnames/example.com/email/.qmail: No such file or directory)

• The following file is missing:

  # stat /var/qmail/mailnames/.default_delivery
  stat: cannot stat '/var/qmail/mailnames/.default_delivery': No such file or directory

Cause

Missing file /var/qmail/mailnames/.default_delivery

Resolution

1. Connect to the server via SSH.

2. Run the Plesk Repair Mail utility:

   # plesk repair mail -y